1. Field of the Invention
The present invention relates to a dispensing apparatus and an in-duct bubble presence determining method in the dispensing apparatus.
2. Description of the Related Art
Conventionally, a dispensing apparatus which is used in dispensing a liquid sample including a specimen or a reagent in an analyzing device absorbs and discharges a liquid, for example cleansing water, in a duct by using a supplying/discharging pump, so that the liquid sample is absorbed through a dispensing nozzle connected to the duct and the absorbed liquid sample is discharged and dispensed to a predetermined position. On this occasion, when a bubble is mixed into the cleansing water, the dispensing apparatus comes to have a lower precision in dispensing the liquid sample due to the bubble. For this reason, the dispensing apparatus fills the duct with deaerated cleansing water.
However, when parts connected to the duct are detached and attached for maintenance and the like, there is a case where a little bubble gets mixed in the duct. In this case, there is a possibility that the dispensing precision in the dispensing apparatus deteriorates without someone's knowledge since the bubble cannot be found easily.
In response to this, a dispensing apparatus having a function of detecting the presence of a bubble in a duct has been proposed (see Japanese Patent Application Laid-Open No. 2003-254982, for example).